Effects of Vitamin K on Lower-extremity Function in Adults With Osteoarthritis:

NCT ID: NCT05505552

Last Updated: 2025-09-17

Basic Information

• Recruitment Status: ACTIVE_NOT_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 37 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2023-09-20
• Study Completion Date: 2026-12-31

Brief Summary

The overall goal of this pilot randomized trial is to obtain necessary prerequisite data to conduct a randomized controlled intervention to test the effect of vitamin K supplementation on knee osteoarthritis progression and related functional decline. To address critical parameters required to design this larger RCT, we will conduct a double-blind, 2-armed, parallel-group intervention study, with a placebo run-in, in which 50 adults with mild to moderate knee OA and low baseline vitamin K status will be randomly assigned to 1 mg phylloquinone/day or matching placebo, and treated for 6 months. Specifically, we will: (1) compare the effects of 1 mg/day phylloquinone vs. placebo on the non-functional circulating form of MGP; (2) estimate rates of recruitment and retention, follow-up rates and reasons for loss to follow-up, response rates to questionnaires, adherence/compliance rates, and potential for site differences; and (3) determine the responsiveness of the Osteoarthritis Research Society International (OARSI)-recommended performance-based tests of physical function in adults with low vitamin K status and mild to moderate knee osteoarthritis. We will also obtain preliminary data on the distribution of MGP genotype at two clinical sites for effect size generation.

As of February 2025, based on attrition rate below what was initially expected, we revised our planned enrollment from 50 to 35, to achieve the original goal of 30 completers. This was approved by the study sponsor.

Conditions

Osteo Arthritis Knee

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: OTHER
• Blinding Strategy: QUADRUPLE

Study Groups

Vitamin K

Participants receive 1 mg/d phylloquinone orally for 24 weeks

Group Type: EXPERIMENTAL

Vitamin K

Intervention Type: DIETARY_SUPPLEMENT

1 mg/day phylloquinone (vitamin K1)

Placebo

Participants receive daily placebo matching phylloquinone for 24 weeks

Group Type: PLACEBO_COMPARATOR

Placebo

Intervention Type: DIETARY_SUPPLEMENT

Placebo capsule once daily

Interventions

Vitamin K

1 mg/day phylloquinone (vitamin K1)

Intervention Type: DIETARY_SUPPLEMENT

Placebo

Placebo capsule once daily

Intervention Type: DIETARY_SUPPLEMENT

Other Intervention Names

Phylloquinone

Eligibility Criteria

Inclusion Criteria

• Age ≥ 50 years
• Male or post-menopausal female (no menses in the last year)
• Plasma phylloquinone <1.0 nmol/L
• Chronic knee discomfort based on affirmative response to the question "During the past 12 months, have you had pain, aching, or stiffness in or around your knee(s) on most days for at least one month?"
• Kellgren-Lawrence (KL) grade 2-3 in at least one knee
• Ability to understand study procedures and to comply with them for the entire length of the study
• Ability to answer questions by phone
• Ability to swallow capsules

Exclusion Criteria

• KL grade 4 in at least one knee
• Inability to walk
• Cognitive impairment (based on a Montreal Cognitive Assessment Test score ≤ 17)
• Widespread pain
• Malabsorption disorders (e.g. advance liver disease, stage 4 or 5 chronic renal disease, Crohn's disease, celiac sprue)
• Serious medical conditions or impairments that, in the view of the investigator, would obstruct study participation
• Plan to permanently relocate from the greater Boston, MA or Chapel Hill NC areas during the trial period
• Planned knee or hip arthroplasty during the study period
• Undergoing cancer treatment
• < 50 years old
• Circulating phylloquinone ≥ 1.0 nmol/L
• Warfarin (Jantoven) use
• Use of other investigational drugs
• Use of herbal, botanical or vitamin K supplements
• Use of assistive walking devices

• Minimum Eligible Age: 50 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of North Carolina, Chapel Hill

OTHER

Sponsor Role: collaborator

Tufts Medical Center

OTHER

Sponsor Role: collaborator

University of Massachusetts, Worcester

OTHER

Sponsor Role: collaborator

Tufts University

OTHER

Sponsor Role: lead

Responsible Party

Sarah Booth

Senior Scientist and Center Director

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Tufts University

Boston, Massachusetts, United States

UMass Memorial Medical Center

Worcester, Massachusetts, United States

University of North Carolina Chapel Hill

Chapel Hill, North Carolina, United States

Countries

United States

Other Identifiers

R21AR080297

Identifier Type: NIH

Identifier Source: org_study_id

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